Hi - I haven't had any problem with keeping the wood cage i built for my two ferrets clean. It has several layers of varnish on it which makes it easy to clean with 409 and water. We have used the cage for three years and haven't had a problem with odor. We just make sure we clean it at least every two weeks. I suggest building a wood cage over metal cages simply because i haven't seen any metal cages at pet stores that I thought would work well for a ferret. I don't like the cages with wire bottoms just because I wouldn't want to walk on wire all the time and since they use a litter pan there is no need for a wire bottom. I have seen maybe one metal cage that i thought was suitable for a ferret but for alot less money I built my own cage. Kristin [Posted in FML issue 1273]